Commitments and Contingencies (tables)

6 Months Ended

Jun. 30, 2011

Commitments and Contingencies Disclosure Abstract

Schedule Of Environmental Loss Contingencies By Site Text Block

			Current Liabilities						Non-Current Liabilities
			June 30,		June 30,		Dec. 31,		June 30,		June 30,		Dec. 31,
Thousands			2011		2010		2010		2011		2010		2010
Gasco site		$	10,593	$	7,996	$	11,366	$	38,965	$	43,522	$	38,921
Siltronic site			836		724		720		71		358		201
Portland Harbor site			2,161		1,836		2,304		5,426		6,875		5,784
Central Service Center site			5		5		5		543		510		510
Front Street site			-		72		1		823		166		1,097
Other sites			-		-		-		132		117		108
	Total	$	13,595	$	10,633	$	14,396	$	45,960	$	51,548	$	46,621

Environmental Regulatory Assets [Text Block]

			Non-Current Regulatory Assets
			June 30,		June 30,		December 31,
Thousands			2011		2010		2010
Gasco site		$	78,270	$	71,531	$	74,205
Siltronic site			3,502		3,068		3,174
Portland Harbor site			35,379		32,712		33,940
Central Service Center site			612		551		553
Front Street site			2,067		1,056		2,020
Other sites			455		406		420
	Total	$	120,285	$	109,324	$	114,312